Feat wise he fought hawkins, killer, apoo, kaido, king. If we talk bounty wise only It was not just the scar, he saved the others from the Hakai and he protected luffy while he was unconcious. You cant tell he " just sccared kaido", its not like anyone else in the whole alliance could do it and if it was the other way around and instead of zoro there was sanji at the rooftop, the sanjifans would go frenzy.
Sanji saved Momo, and Momo is the leader of Wano, which is much more important than what Zoro did
Oh, more importantly, Sanji protected Zoro
